Method of reclaiming soiled solvent by distillation and adsorption



Oct. 29,1946.. E. l.. LuAcEs METHOD OF RECLAIMING SOILED SOLVENT BYDISTILLATION AND ADSORPTION Original Filed March l, 1943 ATTORNEYSPatented ct. 29, 1946 METHOD OF RECLAIMING SOILED SOLVENT BYDISTILLATION AND ADSORPTION` Enrique L. Luces, Dayton, Ohio, assignor toChemical Developments Corporation, Dayton, Ohio, a corporation of OhioOriginal application March 1, 1943, Serial No. 477,683. Divided and thisapplication October 16, 1943, Serial No. 506,502

3 Claims. l

Thi-s invention deals with a method of reclaiming soiled solvent, andthis application is a division of application Serial No. 477,683, i'lledMarch l, 1943.

In particular, this invention deals with a method of reclaiming solventssoiled with coloring matter and containing substantially 20 to 50% ofhydrocarbons and the remainder consisting of ketones, esters andalcohols, any of the latter compounds alone or a mixture thereof. Suchsolvents, for example, are obtained in de-inking Cellophane wastematerial by extraction, as it is described in the above-mentioned parentapplication.

According to the instant invention, solvents of the describedcomposition are reclaimed by adding water and purifying the aqueousfraction formed, after separation, by distillation and the non-aqueousfraction by adsorption with active carbon.

In the following, the method of my invention will be described indetail.

Most of the dyes or colors used in printing Cellophane are insoluble inwater. The solvents used for de-inking may thus be reclaimed for furtheruse by the following procedure:

A quantity of water equal to from 50 to 100% of the volume of the soiledsolvent is added thereto and the mixture slowly agitated. The insoluble(hydrocarbon) portion of the solvent quickly separates from the watermiscible (non-hydrocarbon) portion thereof. 'I'he ink colors aregathered into the supernatant layer of in-soluble or immiscible solventwhile the water added collects in the bottom layer. If severe agitationis avoided the separation of the two layers will be sharp and noemulsication will appear.

.The top and bottom layers are separated. The former is mixed with asmall quantity of active carbon (0.5 to 3% by weight) and after thoroughagitation for approximately to 20 minutes at room temperature may beseparated from the carbon by filtration or otherwise perfectly clear andfree of color. The bottom layer, in turn, is de-watered by distillation.All solvents are thus recovered for re-use with only slight handlinglosses.

It will be understood that While there have been described herein andillustrated in the drawing certain preferred embodiments of thisinvention, it is not intended thereby to have this invention limited toor circumscribed by the specific details herein described in view of thefact that the invention is susceptible to modifications depending onindividual conditions and preference without departing from the spiritof this disclosure and the scope of the appended claims.

I claim:

1. The method of reclaiming soiled solvent containing water-insolublecoloring matter and said solvent consisting of 20 to 50% hydrocarbonsand the balance being selected from the group consisting of ketones,esters, alcohols, and mixtures thereof, said method consisting in addingto the mixture of solvents a quantity of water whereby separation intotwo layers is brought about, the top layer containing the coloringmatter and the bottom layer containing the added water, separating thetop layer and the Ibottom layer, adding to the top layer active carbon,agitating the mixture of active carbon and top layer material, removingthe active car-bon therefrom to obtain top layer material free fromcoloring matter, and de-watering the bottom layer by distillation toobtain bottom layer material free from water.

2. The method of reclaiming solvent consisting of 25% 'benzol, 75%acetone and soiled by waterinsoluble coloring matter, said methodconsisting in adding to the mixture of solvents a quantity of waterwhereby separation into two layers is broughtl about, the top layercontaining the coloring matter and practically al1 of the benzol and theybottom layer containing the added water and practically all of theacetone, separating the top layer and the bottom layer, adding to thetop layer active carbon, agitating the mixture of active carbon and toplayer material, removing the active carbon therefrom to obtain benzolfree from coloring matter, and de-watering the bottom layer bydistillation to obtain water-free acetone.

3. The method of reclaiming soiled solvent containing water-insolublecoloring matter and said solvent consisting of 20 to 50% hydrocarbonsand the balance being selected from the group consisting of ketones,esters, alcohols, and mixtures thereof, said method consisting in addingto the mixture of solvents a quantity of Water whereby separation intotwo layers is brought about, the top layer containing the coloringmatter and the bottom layer containing the added water, separating thetop layer and the bottom layer, adding to the top layer from 0.5 to 3%by weight of active carbon, agitatingthe mixture of active carbon andtop layer material, removing the active carbon therefrom to obtain toplayer material free from coloring matter, and de-water- 'ing the bottomlayer by distillation to obtain bottom layer material free from water.

ENRIQUE L. LUCES.

